Psoriatic Arthritis
Jill C. Cash and Julie Barnes
Definition
A.Psoriatic arthritis (PsA) is a systemic inflammatory condition that occurs in the joints that presents with symptoms of joint pain, stiffness, and swelling around the tendons and ligaments. Other symptoms include psoriasis and inflammatory back pain. PsA is a chronic disease and, when left untreated, can cause irreversible joint damage.
B.Five different types of PsA:
1.Symmetrical polyarthritis.
2.Asymmetric oligoarthritis (fewer than four joints involved).
3.Distal interphalangeal (DIP) joint involvement.
4.Arthritis mutilans (destructive and deforming, causes resorption of the phalanges).
5.Axial arthritis (spondyloarthritis).
C.The 2006 Classification of Psoriatic Arthritis (CASPAR) was developed to assist in diagnosing patients with PsA. The patient must score at least three points from the following list:
1.Skin psoriasis:
a.Present: 2 points.
b.Previous history of skin changes: 1 point.
c.Family history of psoriasis if patient not affected: 1 point.
2.Nail lesions (onycholysis, pitting): 1 point.
3.Dactylitis (present or past): 1 point.
4.Rheumatoid factor (RF): negative: 1 point.
5.X-ray evidence of new bone formation near a joint: 1 point.
Incidence
A.Occurs in approximately 1% to 2% of the U.S. population.
B.It is estimated to occur in approximately 4% to 30% of patients diagnosed with psoriasis.
Pathogenesis
A.Individuals are genetically susceptible to PsA. It is thought that the immune system is triggered by something in the environment, which may include infection and/or trauma. The immune system is stimulated, activating T-cells that produce inflammatory cytokines and mediators that attack the joints, causing inflammation, pain, and/or erosions that can potentially destroy the joint. When this occurs in the joint, damage to the ligament and/or tendon attachment area occurs (enthesis) as well as producing bone spurs and changes in the skin and/or nails.
Predisposing Factors
A.Gender: Men and women are affected equally.
B.Commonly seen in adults ranging from 30 to 55 years of age.
C.The patient has a first-degree relative with psoriasis.
D.More common in Caucasians than African American and Native American populations.
Common Complaints
A.Pain and stiffness in joints, usually lasting longer than 30 minutes in the morning after wakening.
B.Pain and stiffness that usually improves with activity.
C.Enthesopathy (pain and inflammation at the ligament or tendon attachment site of the bone, commonly seen on the Achilles tendon, plantar fascia, or tibial tuberosity area).
Other Signs and Symptoms
A.Skin and nail psoriasis, nail pitting.
B.Uveitis.
Subjective Data
A.Does the patient have a history of skin rash, plaques, and so forth? If present, ask the patient when psoriasis began. What treatments have been used, including topical, light therapy, oral, and subcutaneous treatments?
B.Does the patient complain of photosensitivity?
C.Ask the patient to describe joint changes, such as swelling, pain, redness, and so forth. What joints are affected with pain and swelling?
D.Have any treatments used for psoriasis improved joint pain?
E.What medications or treatments are being used for the joint pain and swelling? What is the result of medications/treatments being used?
F.Does the patient have a history of back pain? If so, when did symptoms begin? Ask the patient to describe his or her back pain. Does pain improve or worsen with physical activity?
G.Does the patient have a history of frequent infections or high fevers?
H.Any history of frequent eye infections?
Physical Examination
A.Check vital signs and temperature as indicated.
B.Inspect:
1.Inspect the skin for plaques or rash.
2.Inspect the nails for pitting.
3.Inspect the joints for inflammation, synovitis, and erythema.
4.Inspect the eyes for erythema and injection.
C.Auscultate:
1.Heart.
2.Lungs.
D.Palpate:
1.Palpate all joints (hands, wrists, feet, elbows, ankles, knees, and shoulders) for synovitis/pain:
a.Dactylitis (swelling of the entire finger/toe that appears as a sausage digit
) occurs in approximately 50% of patients diagnosed with PsA.
b.Enthesopathy is commonly seen in the Achilles tendon, plantar fascia, or tibial tuberosity.
2.Note range of motion (ROM) of all joints.
3.Palpate lumbar/thoracic spine.
4.Palpate sacral/iliac joint for tenderness.
Diagnostic Tests
A.Erythrocyte sedimentation rate (ESR): May be elevated or normal.
B.C-reactive protein (CRP): May be elevated or normal.
C.Complete blood count (CBC).
D.RF: Commonly negative in these patients; only 2% to 16% of patients with PsA will have a positive RF.
E.X-rays of affected joints.
Differential Diagnoses
A.PsA.
B.Rheumatoid arthritis (RA).
C.Ankylosing spondylitis (AS).
D.Osteoarthritis (OA).
E.Gout.
F.Reactive arthritis.
Plan
A.General interventions:
1.Early identification is necessary to prevent irreversible joint damage.
B.Patient teaching:
1.Nonpharmacological treatment options include the following:
a.Exercise on most days of the week. ROM exercises are encouraged for joint stiffness.
b.Heat application for stiffness and ice to affected joint for swelling may be used.
c.For extended joint stiffness/pain, recommend physical therapy for assessment and treatment.
C.Pharmaceutical therapy:
1.First-line treatment: The European League Against Rheumatism (EULAR) recommends the use of nonsteroidal anti-inflammatory drugs (NSAIDs) for first-line treatment. Precautions should be given for all patients using NSAIDs (cardiovascular, renal, and GI risks should be considered). NSAIDs are used for mild symptoms.
2.Second-line treatment: Disease-modifying antirheumatic drugs (DMARDs), such as methotrexate (MTX), sulfasalazine, and leflunomide, are used. These medications should be prescribed by a rheumatology specialist.
3.Third-line treatment: Biological tumor necrosis factor (TNF) inhibitors (adalimumab, certolizumab pegol, tanercept, golimumab, and infliximab). These medications should be prescribed by a rheumatology specialist.
Follow-Up
A.Follow-up is recommended in 2 weeks if prescribing NSAIDs for treatment of early disease.
B.Recommend follow-up every 3 months if not referred to rheumatology.
Consultation/Referral
A.Patients diagnosed with PsA who are not controlled with NSAIDs or who have evidence of joint changes should be referred to a rheumatology specialist for evaluation and treatment. NSAIDs do not prevent joint damage and prevention of irreversible joint damage is imperative.
B.Patients presenting with uveitis should be referred to an ophthalmologist for evaluation and treatment.
C.Patients diagnosed with severe joint damage should be referred to orthopedics for evaluation and treatment options (surgery).
D.Patients diagnosed with severe skin psoriasis should be referred to dermatology for evaluation and treatment.
Individual Considerations
A.Adults:
1.The use of oral steroids is not recommended for patients with PsA. Oral steroids have not been found to be effective; they also present a high risk of skin psoriasis flare when tapering the steroid dose.
2.Patients diagnosed with PsA are at higher risk for cardiovascular disease (CVD) and should be screened and monitored annually.
B.Geriatrics.
1.When prescribing NSAIDs, monitor renal, cardiac, and GI systems for adverse events with use.